The Molecular Biology and Cell Culture Core will provide a centralized facility for carrying out all site-directed mutagenesis experiments, construction of new expression plasmids and creation of bacterial and baby hamster kidney cell lines expressing the desired proteins required by the P.I.s of the four projects. Construction of plasmids for e3xpression of new serpins will be done in consultation with the appropriate P.I. The core will occupy common space with the Protein Expression and Purification core. The Administrative Director will be responsible for overnight of the core and for ensuring equitable service to all of the projects.